I disagree. The Jundland Wastes or the cool rocky outcroppings we see in Anakin's search, are magnificent and brilliant.
Also, some of the giant creatures on Tatooine (especially the one who's skeleton is behind Threepio in ANH) are dangerous and menacing.
So visually the worst...it's that vs Dagobah, since we have no idea of scale.
As I gaze up at the night sky in my own fair time, I look back down and see the devastation. This post-nuclear world. It's terrible. But at least we got Nuka-Cola, warm and flat, the drink of the post-apocalyptic civiliztion. Generation Next!